Brake release mechanism for presses



NOV. 14, 1933. LOSHBQUGH 1,934,984

BRAKE RELEASE MECHANISM FOR PRESSES Filed March 7, 1930 2 Sheets-Sheet 1 rmgy.

NOV. 14, 1933. J, LOSHBQUGH 1,934,984

BRAKE RELEASE MECHANISM FOR PRESSES Filed March 7, 1930 2 Sheets-Sheet 2 lmingsb Referring to the details of the drawings the.

' fly-wheel being adapted to be r eleasably clutched r Patented" Nov. 14, 1933 r l PATENT oFFIJCB 7 My invention relates to power presses, and particularly to the brake mechanism therefor.

In'power presses the crank-eshaft rotation, which operates the press ram, is retarded or 5 stopped by a friction brake which imposes a continuous load thereon for the full revolution fof thecrank-shaft, and such a condition in the press requires more power to operate the press than would be necessary if the brake functioned 10 for a fraction only of each revolution of the crank-shaft. I a i The principal object of this invention is to provide brake release means to relieve the crankshaft of a power press of the'brake load or innuenceror a portion of each, revolution of the crank-shaft;thereby-economizing in power and materially reducing the degree of heat generated in the brake.

Other and more specific objects-of the inven- 'tion are mentioned and suggested by the mechanical disclosures herein.

The preferred embodiment of my inventionis illustrated in the wherein press "to which my invention isapplied; 1

'Fig; 2Iis a side elevation thereof, partially broken away; f

Fig. 3 is a fra'gmental 'view in elevation of the 0 upper end of the press whichjcirriesthe crankshaft brake mechanism;

" Fig. 4 is a similar View; partially in section;

; Fig; 5 is a section taken on line 5-5 of Fig. 4;

Fig. 6 is'a-section taken on line 6-6; of Fig. 4;and v f' Figfi'l is a perspectiveview of the 'brakeactuating'lever.

Similar numerals ofreferenceindicate like parts'throughoutthe} several views on the drawnumeral 1 represents the press main frame in which is mounted the reciprocatory-ram 2-which is operatively connected with the pitman 3, the

crank4 of the conventional crank-shaft. 5 which is rotatably mounted in the press frame. The

shaft, 5' maybe driven-by any suitable" power means, but in thedrawings an electric motor 6 is'"illustrated as 'asource of power for rotating the fly-wheel I,normally loose on shaft. 5,. said to 'the 'shaft 5 by a spring pressed "sliding clutch 48 under the control of the; usualtiltable detent cam lever 49 which is retractable by'link50, the latter being operatively connected with the outer end of the lever 14, and operative thereby, as hereinafter described. 7 v

The numeral 8 indicates a spring 'retractedfoot pedalpivotally'mounted in the press base 10 at accompanying drawings,

Figure 1 is afront elevational view of a power latter being' operatively 'co nnected with theusual I 9, depression of said "-pedalbeing adapted to control'the operation of "the press, as 'is well known, said pedal being associated with the upright link elementvll which has-its lower end connectedtherewith at 12, the upper endof said link being operatively connected with the de-,

pending element 13 which is connected with the downwardly tiltable lever 14 which has its end pivotally mounted in the press frame at 15. 7

The numeral 16 indicates a horizontal rock- -shaft journalled in the'frarrie land extending transversely therethrough behind the ram 2, one

end of said shafthaving the lever arm 17 rigidly connected therewith, and the opposite end there- 'of having a similar leverarm 18' rigidly connected.

therewith. The lever l'lis arranged above the lever 14 andconnected therewith by a link 19, whereby, when pedal 8 is depressed, the arm 17 is downwardly tilted, therebyrocking shaft 16 and downwardly tilting "lever arm 18.

The numeral 20 indicatesa cylindrical brak drum rigidly mounted on and adjacent the end of shaft 5 and emcompassed by the split, two piece brake band. 21 which comprises the two arcuate half sections 22 and 23 hinged together at 24and rigidly mounted inthe press frame by lug -25,

integral with brakeband section 22; which is mounted upon the anchorage stud or bolt,26.rigid with thepress frame. Normally, the brake band 21 is-yieldably clamped about the drum 20, but the hinge element at 24 enables brake release from the drum by spreading thG'tWOSE Ct iOIIS 22 and 23, as hereinafter described. The clamping action of brake band 21 is effected by'the fcom:

,pression coil spring 27. carried on the stud 28 which has its lower end rigidly mounted in the lug 29 of band section 23, andwhich extends loosely through aperture 30 in lug.31'of band section 22, saidspring being compressed between saidlug 31 and the adjustable nut 32 which is screwthreaded uponthe upper end of the stud 28. Regulationof the tension of spring 27 may be made by the adjustment of the nut 32=longitudinally of stud 28; P Spreadingof .thejtwo band sections 22 and 23 to relieve drum 20 of the brake friction thereonis accomplishedby a forked lever 33 and link'34.

'which is connected with the outer end. of the tiltablelever arm 18. 7 The end, of each' of thetwo forksof lever 33 gains a pivotal .bearing'on a pin 35 mounted, in

the brake band lug 29, said pin engaging in fork apertures36 and 37V of said lever, each of: j

said' fork'ends having a relatively short lateral lever'farm; 38 and 39 respectively, projecting therefrom; A "bearingrollerlo is rotatably mountedbetween'the lever arms 3'7and 38 on abearing pin41 connecting said arms adjacent the v outer ends thereof,*said roller normally bearing againstftheinner-face of band lug 31 when brake band 21 is compressed about drum 20. In this arrangement of the parts andelements described the spring carrier stud 28 and band lug 31 are disposed between the two forksof the, 1ever'33 with sufficient clearance to permit the free movement of all the elements mentioned. v

The top end of the link 34 may have a hooklike connection with an aperture 42 formed in the extremity of the lever 33, and the-lower end of said link may be adjustably mounted in a block 43 which is pivotally mounted in the endof lever 18. The block 43 hasa lateral stud 44 in tegral therewith which is pivotally mounted in an aperture 45 formed transversely in the end of lever 18, and link 34 is screwthreaded through the block body 43, to enable adjustment thereof in'said block. Jaminuts 46 and 47 are threaded upon link 34 above and below the block 43 to maintain the vertical adjustment of said block, and a cotter key 51 in stud 44 prevents displacement of said stud from its bearing aperture-45.

Vertical adjustment of the link 34 in block 43 brake retardation. 7

It will also be evident from: the foregoing that the brake drum 20' is disengaged from the brakeband section 23 as long as the pedal 8 is held depressed by the operator, and that, upon release of said pedal, the brake band section 23 is caused to reengage the brakedrurn by action of the spring 27.

Iclaim: l.

1'. The combination with'a powerpress proe vided with a driven shaft, a clutch for actuating said shaft, and mechanism for shifting said clutch including a depressible pedal, of a brake for said shaft and including a-drum'rigid with said'shaft, and a pair of arcute brake band members encompassing said drum and normally spring presses into engagement therewith, said brake band members having spaced adjacent ends provided with laterally projecting lugs, and means for releasing said brake band members from said drum, said 'means comprising a shiftinglever pivotally mounted in oneof said brake band lugs and between said brake band lugs, said shifting lever being-provided with a lateral arm which coacts with the brake band lug opposite the lug in which said lever is mounted, and means connected with said pedal for tilting said shifting lever and operative upon depression ofsaid pedal. I, g 2. The combination with, a power press provided with a driven shaft, a clutch for actuating said shaft, and mechanism. for :shifting said clutch including a de ressible pedal," of abrake for said shaft and including adrum rigid with said shaft, and a pair of arcuate brake-band members encompassing said drum and normally springpresse'd into engagement therewith, said brake band members having spaced -adjacent ends, and means for releasing said'brake-band members from said drum, said means comprising a furcated shifting lever pivotally mounted in theend of one of said brake-band members and between said brake bandends, each iork of said vided with a driven shaft, a: clutch foractuating vided with a driven shaft, a clutch for actuating said shaft, and mechanism for shifting said clutch including adepressible pedal, of a brake forsaid' shaft and including a drum. rigid with said shaft, and a pair of arcuate brake-band members encompassing said drum and normally spring pressed into engagement therewith, said brake-band members having spaced adjacent ends-and means for, releasing said brake-band nected with said. pedal for tilting said shifting lever and operativev upon depression of said pedaLsaid means including a rock-shaft mounted in the press frame, a lever arm on saidrockshaft, linkage connecting said rock-shaft with said pedal, and an adjustable link connecting said lever arm and shifting lever. I

4.- The combination with a power press prosaid shaft, and mechanism for shifting said clutch including a; depressible pedal, of a brakedrum rigidly mounted on said shaft, a pair of arcuate brake-band members mounted in the press frame,

encompassing said drum and normallyspring 119 pressed into engagement with said brake drum, said brake-bandmembershaving spaced adjacent ends, means for releasing said brake-band members from said drum, said means comprising-ta shifting lever. pivotally mounted in the end of one of said brake-band members-and provided with-a pair of lateral arms and a roller mounted upon said'lateral arms, said roller engaging the end of the otherbrakerband member, and means connectedwith said pedal for tilting said shifting 1- 0 lever and operative upon depression-ofsaid pedal.

5. The combination with a power press provided with a driven-shaft, -'a clutch for actuating said ish'aft, and mechanism--ior shifting, said clutch including a depressible pedal, of abrake for said shaft and-including a; drum rigid with said shaft, and a pair of arcuate brake-band members encompassing said drum and normally spring pressed into engagement therewith, said brake-band members having spaced adjacent ends, and means for releasing said brake-band members from said drum, said means comprising 

